1. Field of the Invention
The present invention relates to an extraction and purification method of active constituents from honeysuckle (Lonicera japonica Thunb.) and its use, more particularly to an extraction and purification method of active constituents including sweroside from honeysuckle stem (stem of honeysuckle where leaves are removed) by removing tannins, hardly soluble flavonoids, saponins, and the like. Thus obtained active constituents have better anti-inflammatory and analgesic effect, are safer and more stable than the conventional active constituents obtained from honeysuckle flower or honeysuckle leaves, and include sweroside which is an effective active ingredient of anti-inflammatory and analgesic drug.
The honeysuckle (Lonicera japonica Thunb.) is a semi-evergreen viny shrub that grows naturally at the feet of mountains or levees in the range of an altitude of 50 to 600 meters in Japan, China and Korea. Its flower bud (honeysuckle flower) and stem (honeysuckle stem) are used as herbal medicines for promotion of urination, detoxification, hemostasis, blood purification, treatment of tumor, edema treatment, cold, diarrhea, emesis, and the like [Illustrated Book of Korean Flora, Chang-Bok Lee, 709, 1989, Hangmun Publishing Co., Seoul; Standard for Herbs (Herb Medicines) Not Covered by Korean Pharmacopoeia, Hyung-Joon Chi, Sang-In Lee, 87, 305, 1988, Korea Medical Index Co., Seoul; Resource Plants in Korea, Tae-Kyung Kim, vol. 4, 148-149, 1996, SNU Press, Seoul]. Also, many traditional Chinese medicinal books including Sasang Constitutional Medicine and Gwangje Bigeup teach that it is good for treating a variety of inflammatory abscesses inside and outside human bodies [Sasang Constitutional Medicine for Chosun People, Yenben Chosun Medical Institute, 276, 1991, Yeogang Publishing Co., Seoul; Gwangje Bigeup, Kyung-Hwa Lee, 349-351, 1991, Yeogang Publishing Co., Seoul]. It has long been used as a folk remedy for treatment of upper respiratory infections such as cold, tonsillitis and neuralgia for its anti-inflammatory and analgesic activity. Recently, the inflammatory and analgesic activity of honeysuckle has been proved through a variety of experimental animal models, and its effective physiologically active constituents have been isolated and reported to the academic circle [Development of the vegetable anti-inflammatory medicine: Comparison of anti-inflammatory and analgesic actions of the honeysuckle extract, Song-Jin Lee et al., Korean Journal of Pharmacognosy, 363-367, 25, 1994; Flavonoids from the aerial parts of Lonicera japonica, Son et al., Arch. Pharm. Res., 365-370, 15, 1992; Antiinflammatory activity of Lonicera japonica, Lee et al., Phytother. Res., 445-447, 12, 1998; Triterpenoid saponins from the aerial parts of Lonicera japonica, Son et al., Phytochem., 1005-1008, 35, 1994 ; Anti-inflammatory activity of the major constituents of Lonicera japonica, Lee et al., Arch. Pharm. Res., 133-135, 18, 1995].
2. Description of the Related Art
To date, hydrolyzable tannins such as caffeoylquinic acid, methyl caffeate, chlorogenic acid and iso-chlorogenic acid, and iridoid glycosides such as loganin, sweroside, vogeloside and epi-vogeloside are known as effective active constituents contained in honeysuckle stem. Most conventional researches have been centered on honeysuckle flower and honeysuckle leaves. It should be noted that honeysuckle stem has a different distribution of constituents from honeysuckle leaves or honeysuckle flower. That is, unlike honeysuckle stem, major constituents of honeysuckle leaves or honeysuckle flower are flavonoids, such as lonicerin, rhoifolin and ochnaflavon, triterpene saponins having hederagenin or oleanolic acid as non-sugar constituent, and various hydrolyzable tannins.
These constituents are hard to be prepared into an injection. If the injection is rich in polymer tannins, they may bind to other constituents thus resulting in coprecipitation, and may bind to serum proteins in the blood to form hardly soluble precipitates, which can be a cause of angiostenosis. In addition, since flavonoids included in honeysuckle in general are insoluble to water, a fairly large amount of organic solvent or other agents which mediate dissolution are necessary to dissolve them to the level higher than the effective concentration. Also, active constituents rich in flavonoids are extremely insoluble in physiological salt solution for injection and may become unstable if stored for a long time in an alkaline buffer solution. Lastly, saponins obtained from honeysuckle, particularly monodesmosides, are known to have strong hemolysis properties. Therefore, they cannot be injected directly into the vein without purification [Studies on the saponins of Lonicera japonica Thunb., Kawai et al., Chem. Pharm. Bull., 4769-4775, 36(12), 1988]. Honeysuckle leaves and honeysuckle flower are greater in tannins and hardly soluble flavonoids than honeysuckle stem. In the acute toxicity test for injections, they confer more toxicity than honeysuckle stem even at low contents, and provide poor analgesic and anti-inflammatory effect.
Lonicera japonica, Swertia japonica, Gentiana scabra, Gentiana triflora, Gentiana manshurica, Gentiana rigescens, and Gentiana rigescens French. var. stictantha Marquand have been used for alleviation of fever or detoxification for many years. However, it has not been clearly understood which constituents offer such effects, and most of the researches have been concentrated on identifying the activities of loganin, the major medicinal ingredient of honeysuckle stem [J. Nat. Prod., 54(4), 1102˜1104, 1991: Planta Med., 60, 232˜234, 1994: Phytotherapy Res., 12, 405-408, 1998].
Further, sweroside has been known as effective only in liver protection and inhibition of bacterial activity [J. Ethnopharmacol., 42, 183-191, 1994: Chem. Pharm. Bull., 45(11), 1823-1827, 1997: Yakugaku Zasshi, 102(8), 755-759, 1982], and its anti-inflammatory and analgesic effect has not been reported so far.